gistfile1.txt

type marshalled_location = {.
"administrative_area_level_1": string,
"country": string,
"locality": string, "postal_code": string,
"route": string,
"street_number": string
}

type input = {
key: string,
id: string,
placeholder: string,
input_type: string,
location: option(marshalled_location)
}

module Encode = {
 let location = (location: location) =>
   Json.Encode.(
     object_([
       ("administrative_area_level_1", string(location.administrative_area_level_1)),
       ("country", string(location.country)),
       ("locality", string(location.locality)),
       ("route", string(location.route)),
       ("street_number", string(location.street_number)),
     ])
   );

 let input = (input: input) =>
   Json.Encode.(
     object_([
       ("key", string(input.key)),
       ("id", string(input.id)),
       ("placeholder", string(input.placeholder)),
       ("input_type", string(input.input_type))

     ])
   );

   let locations = (inputs) => {
    let marshalled = List.map((i: input) =>
    input(i)
    ,
    inputs,
    );
    marshalled
   };
}


let request = (websocket_id, inputs) =>
{
  let encoded_locations = Encode.locations(inputs);
  let payload = Js.Dict.empty();
    Js.Dict.set(payload, "id", Js.Json.string(websocket_id));
    Js.Dict.set(payload, "locations", Js.Json.string(inputs));

    Js.Promise.(
      Fetch.fetchWithInit(
        "/query",
         Fetch.RequestInit.make(
          ~method_=Post,
          ~body=Fetch.BodyInit.make(Js.Json.stringify(Js.Json.object_(payload))),
          ~headers=Fetch.HeadersInit.make({"Content-Type": "application/json"}),
          ()
        )
      )
      |> then_(Fetch.Response.json)

    )
    |> ignore;
};

/// output in console 

(2) [{…}, Array(2)]
0:
id: "pickup_address"
input_type: "pickup"
key: "0"
placeholder: "address 0"
__proto__: Object
1: Array(2)
0:
id: "dropoff_address"
input_type: "dropoff"
key: "0"
placeholder: "address 0"
__proto__: Object
1: 0
length: 2
__proto__: Array(0)
length: 2